Artcare - Auckland Art Gallery

PhotographsExternal causes of contamination are much morenumerous. The air around us at home or work can carryseveral gases which will cause rapid and irreversibledamage to images; these include sulphur dioxide, hydrogensulphide and acids formed by sulphur dioxide, nitrogendioxide, carbon monoxide and ozone. These andother gases come from a range of sources as common asengine exhausts, factory emissions, house paints, contactadhesives, cleaning products, geothermal activityand office equipment. Minute quantities of these gasescan cause staining or fading in the presence of moisture.Physical contact with other common chemicallyactive materials including wood products, plywood orchipboard, acidic paper envelopes, adhesive labels andpressure-sensitive tape, cleaning materials, insecticidesand fungicides, certain plastics and adhesives, rubberproducts, uncoated steel and inks will also cause damageto images.Light—photographs are susceptible to damage bylight (see also page 3). Colour dye images are more fugitive(prone to fading) than are black and white.Ultraviolet wavelengths, found in abundance in sunlightand fluorescent tubes, are particularly damaging.Physical Damage—abrasion, creases, bends andtears are common symptoms of inadequate physical protectionor support.Biological Attack—photographs provide a richsource of food for insects and mould. Insects such as silverfishreadily eat paper in photographic prints. Mouldcan also make gelatin water-soluble. Human fingerprintswill, over time, cause permanent damage to photographs.HandlingAvoid touching the surface of a photographic print or anegative with your fingers. Permanent damage will eventuallyresult from skin oils and salts. Wash your handsand handle photographs by the edges only. Wearingclean cotton gloves is a good practice.Always treat your negatives with care. If a print islost or damaged, the negative will enable another copyto be made. Keep them cool, dry and dust-free. It is alsoimportant to label the sleeves or envelopes for your negatives.Basic information such as the date, photographer,subject and location, written on the sleeve will preventunnecessary damage through handling and save timewhen you are searching for a particular image. For largecollections particularly, a numbering sequence and catalogueis important.Do not write on the back of prints with ink. Avoidusing pressure-sensitive labels or tape. If it is necessaryto write on the back of a print, use a soft pencil (2B) inthe border area.StorageThe ideal environment to achieve the longest possiblelife-expectancy for photographs is a fairly unattractiveplace for domestic habitation, being dark, dry and cold.Some museums, galleries and libraries maintain specialrooms with constant climate control and air purificationequipment for storing their collections. Individualscan enhance the stability or prevent deterioration oftheir own collections by choosing suitable enclosurematerials and keeping them in a clean, climatically stableenvironment.Tragically, many products commonly used forphotographic storage are unsuitable for long-termpreservation. These products include PVC (polyvinylchloride) plastic storage pages, ordinary paper envelopes,ordinary cardboard, rubber bands, rubber cementadhesives, spray adhesives, glassine negative sleeves andalbums with chemically unstable pages (see also page26). Such materials should be avoided and, if in use, systematicallyreplaced with chemically stable papers, cardand plastics.All negatives and colour transparencies should bestored upright and supported to avoid bending or damageto the emulsion caused by weight pressure. Printsshould be kept flat to enable even physical supportunless they are mounted and framed. If enclosures haveseams, these should face the reverse of the image. Metal25